Hydrobiological constraints of trace metals in surface water, coastal sediment and water lily of Calabar River, Nigeria

Trace metals concentrations in surface water, sediment and water lily (Nymphaea lotus) samples from the banks of Calabar River, a major tributary of Cross River Estuary, Nigeria were determined. The results revealed average concentrations 0.017, 0.010, 37.08 and 0.025 mg/l, respectively, for As, Cd, Fe and Pb in surface water samples, which exceeded Federal Environmental Protection Agency (FEPA) maximum guideline values. Elevated levels of heavy metals (As, 1.251 mg/kg; Cd, 0.038 mg/kg; Co, 0.509 mg/kg; Cu, 3.78 mg/kg; Fe, 35.48 mg/kg; Mn, 10.72 mg/kg; Ni, 0.732 mg/kg; Pb, 1.355 mg/kg; V, 0.427 mg/kg; and Zn, 8.665 mg/kg) in sediment samples indicated anthropogenic influences while, measured concentrations in N. lotus were typical of a growing plant.